Treatment of cellulosic textile fabrics with bisformamide-formaldehyde adducts



United States Patent TREATMENT OF CELLULOSHI TEXTTLE FABRICS gvIIJTHSBZSFORMAMIDE-FORMALDEHYDE Al)- Sidney L. Vail and .lohn G. Frick, Jn, New Orleans, and Wilson A. Reeves, Metairie, La, assignors to the United States of America as represented by the Secretary of Agriculture No Drawing. Filed June 29, 1962, Ser. No. 204,013

6 Claims. (Cl. Ill-139.4)

(Granted under Titie 35, US. Code (1952), sec. 266) A non-exclusive, irrevocable, royalty-free license in the invention herein described, throughout the world for all purposes of the United States Government, with the power to grant sublicenses for such purposes, is hereby granted to the Government of the United States of America.

This invention relates to the treatment of cellulosic textile materials to produce textiles having improved properties. More specifically, the present invention relates to new textile treating agents and a method of treating cellulosic textile fabrics with these agents whereby the fabrics are rendered resistant to wrinkling, have improved resiliency, and possess wash-and-wear properties. Moreover, the finishes produced from the new textile treating agents of this invention were found to be extremely durable. These finishes were found to effectively resist hydrolytic removal under conditions that remove the finishes based on the commonly used N-methylol treating agents.

In general, the production of wrinkle resistant and wash-and-Wear fabrics has been accomplished by the use of diand polyfunctional N-methylol finishing agents. These agents are generally formed by the addition of formaldehyde to ureas (cyclic or straight chain), melamine, and other similar type compounds. However, it is well known that finishes produced from these agents are fairly easily removed by repeated washing procedures which employ moderately strong acidic solutions, that is, the souring step used in most commercial launderings, After such treatments, it is often found that the treated fabric has lost the finish and the desired wrinkle resistance and wash-and-wear properties. Consequently, these treating agents cannot be used to produce acceptable wash-and-wear cellulosic fabrics which are to be subjected to these, or similar, hydrolytic conditions.

In the recent work [American Dyestuff Reporter, 50, No. 12, 29 (1961)] it was shown that N-methylolamides formed from acetamide and formamide produced finishes which were much more resistant to acidic hydrolysis than the finish derived from the N-rnethylol derivatives of ureas. More recently it was found that N-methylol derivatives of bisamides would form finishes on cellulosic fabrics which would prove to be highly resistant to acidic hydrolysis.

In general, alkaline hydrolysis is somewhat less detrimental than acidic hydrolysis under the normal conditions encountered in use.

A primary object of the present invention is to provide methylol derivatives of bisamides which have outstanding characteristics as treating agents for cellulosic textiles.

Another object of the invention is to provide a process for the treatment of textile fabrics, composed mainly of cellulose, with a new type of methylolamide treating agent, whereby the finished fabric acquires the properties of increased resiliency and wrinkle resistance. It is furthermore an object of this invention to provide such a treatment whereby the finish produced is resistant to harsh conditions of acidic hydrolysis and is not susceptible to alkaline hydrolysis. A further object of the present invention is to provide a finished fabric of the above Patented Aug. 3, 1965 desirable properties without suffering excessive fabric damage.

In general, these and other objects of the invention are accomplished by treating the cellulosic textile with an aqueous solution containing themethylol derivatives of bisamides having the following structure:

wherein n is an integer of one to four. As is'evident from the above structural formula the bisamides suitable for use in the present invention must be bisformamides having two amido hydrogens available for addition of formaldehyde. These bisformamides can be obtained economically by procedures well known to those skilled in the art. For example, methylenebisforrnamide can be prepared conveniently by heating formaldehyde and formamide. The other bisformamides can be prepared by diformylation of the particular diamine with formamide, alkyl formates, or other similar formylating agents. It is believed that the bisforrnamides are capable of the addition 'of two molar equivalents of formaldehyde to form a difunctional, or N,N'-dimethylol, derivative. I

The N-methylol derivatives of the bisformamides used for the treatment of the cellulosic textile in the process of this invention can be conveniently obtained by the reaction of formaldehyde with the bisformamide of the above-described structure in aqueous media under slightly alkaline conditions. It is preferred to employ about three molar equivalents of formaldehyde to one of the bisformamide. A smaller quantity of formaldehyde can be used, but it has been found that the smaller quantity (two molar equivalents of the stoichiometric quantity of formaldehyde to produce complete methylolation based upon the number of reactive hydrogens available in the particular bisformamide) does not produce a treated fabric with'the highest wrinkle recovery angle. An amount of formaldehyde significantly in excess of the three to one ratio can also be employed, but it is inefficient and uneconomical to use such a large excess. The other conditions of this reaction are well known in the trade. Generally, heating the aqueous solution of the bisformamide and formaldehyde at 60 C. for 30 minutes is suficient to achieve formation of the methylol derivatives. The reaction products thus produced are water soluble. The solution can be used as is or can be diluted with water for treatment of the cellulosic material.

Prior to application of the agent to fabric, an acidic substance or a substance producing acidity at elevated temperatures'is added to the diluted solution to serve as a catalyst. The concentration of the reactants, i.e., the bisformamide-formaldehyde adduct plus the excess or unreacted formaldehyde, can be varied depending on the particular textile processing conditions used, the type of textile being treated, and the properties desired in the finished textile. Generally, it is preferred to use from about 5% to 20% by weight of the reactants in the diluted treating solution. The catalysts which may be used are well known in the trade. Magnesium chloride, zine fluoborate, and zinc nitrate are examples of particularly suitable catalysts. From about 0.5% to about 5% by weight of the acidic catalyst is generally preferred. 7

Treatment of the cellulosic textile material is carried out by standard procedure. 7 The textile is thoroughly wetted with the above-described treating solution; the excess liquid is mechanically removed, and the wetted textile is dried and cured. Following the curing operation it is preferable, but not absolutely necessary, to waten wash the treated textile in an alkaline solution to remove any unreacted materials.

The processes of thisinvention can be used to treat substantially any hydrophilic fibrous cellulosic material such as cotton, rayon, ramie, jute, and the like which can be impregnated with a liquid, dried, and cured.

The following examples are given by way of illustration and not by way of limitation of the invention. The detailed procedures given below in the examples are illustrative, and are not the only or specific conditions for the production of an acceptable finished textile. Many variations or additions within these procedures can be made, as will be readily apparent to those skilled in the art. In the examples, all parts and percentages are by weight unless noted otherwise. The fabrics were tested by the following methods: Wrinkle recovery angle, Monsanto method, American Society for Testing Materials (ASTM) test Dl'29553T; tearing strength, Elmendorf method, AST M test D1424-59.

EXAMPLE 1 1,3-propanebisformamide was prepared by refluxing 74 grams of 1,3-propanediamine and 300 grams of methyl formate. The excess methyl formate and any low boiling products were removed by distillation. The resultant yellowish oil was further concentrated by a vacum distillation at mm. with a maximum pot temperature of 175 C. The 1,3-propanebisformamide contained 21.36% nitrogen and was found (by osrnometer) to have a molecular weight of 130 (theory for C H N O 21.53% nitrogen and 130 for the molecular weight) EXAMPLE 2 To five grams of the bisformamide was added a slightly alkaline, aqueous solution of formaldehyde such that the molar ratio of formaldehyde to the bisamide was 3:1. The solution was either kept at room temperature for 18-24 hours or heated to 5060 C. for about two hours. Then, two grams of magnesium chloride hexahydrate was added (final concentration was 4%) and the weight of the solution adjusted to a total of 50 grams by the addition of Water. A sample of 80 x 80 cotton print fabric was dipped in the treating solution and padded to give about 70-80% increase in weight. of the fabric. The wet fabric was dried seven minutes at 60 C. and cured for three minutes at 160 C. This treatment was followed by a wash in warm alkaline water, with a nonionic detergent added, and then tumble drying. Using this general procedure, with variations noted where ap propriate, the following bisformamides were used to produce wrinkle resistant fabrics, the properties of which are shown in Table I:

Example 2A. Methylenebisformamide.

Example 2B. Ethylenebisformamide, with a 2:1 molar ratio of formaldehyde to the bisformamide.

Example 2C. Ethylenebisformamide.

Example 2D. Ethylenebisformamide, with a catalyst of 0.8% Zn(BF Example 2E. 1,3-propanebisformamide (as prepared in Example 1).

Table I.Warp properties of treated fabrics EXAMPLE 3 Table II.-Acid hydrolysis of amide finishes Percent of original nitrogen Agent type: retained after hydrolysis As in Example 2A 89 As in Example 2C 100 As in Example 2E 90 Dimethylolurea 5 EXAMPLE 4 The durability of a representative finish, prepared from a methylolbisformamide, to basic hydrolysis was tested by heating the fabric for thirty minutes at C. in a solution containing 1% sodium carbonate. The fabric (as in Example 2A) retained 98% of the original nitrogen after hydrolysis under these conditions.

We claim: 1. A process for producing a wrinkle resistant cellulosic textile material that is resistant to acidic and to basic hydrolysis comprising impregnating a cellulosic textile material with an aqueous material containing from 5 to 20% by weight of the reaction product of at least 2 moles of formaldehyde and 1 mole of a bisformamide represented by the formula:

wherein n is an integer of from 1 to 4, and from 0.5% to 5% by weight of an acidic catalyst and heating the thus impregnated cellulosic textile material to dry and cure it.

2. The process of claim 1 wherein the bisformamide is methylenebisformamide.

3. The process of claim 1 wherein the bisformamide is ethylenebisformamide.

4. The process of claim 1 wherein the bisformamide is 1,3-propanebisformamide.

5. The process of claim 1 wherein the acidic catalyst is magnesium chloride.

6. The process of claim 1 wherein the acidic catalyst is zinc fluoborate.

References Cited by the Examiner UNITED STATES PATENTS 2,562,161 7/51 Epelberg et a1.

2,765,336 10/56 Hurwitz et a1. 260-561 2,819,307 1/58 Albert 260561 2,985,544 5/61 De Monterey et a1. 117-143 2,985,546 5/61 Leavitt l17l43 3,024,135 3/62 Sookne et a1. 117139.4

OTHER REFERENCES J. Org. Chem., vol. 27 (1962), 260-561 (pp. 1062-70 pertinent).

WILLIAM D. MARTIN, Primary Examiner.

IRVING MARCUS, Examiner. 

1. A PROCESS FOR PRODUCING A WRINKLE RESISTANT CELLULOSIC TEXTILE MATERIAL THAT IS RESISTANT TO ACIDIC AND TO BASIC HYDROLYSIS COMPRISING IMPREGNATING A CELLULOSIC TEXTILE MATERIAL WITH AN AQUEOUS MATERIAL CONTAINING FROM 5 TO 20% BY WEIGHT OF THE REACTION PRODUCT OF AT LEAST 2 MOLES OF FORMALDEHYDE AND 1 MOLE OF A BISFORMAMIDE REPRESENTED BY THE FORMULA: 